TWI647231B - Organic electroluminescent material and device - Google Patents

Abstract

The invention discloses a composition formed from a mixture of two compounds having similar thermal evaporation characteristics premixed into an evaporation source. The evaporation source can be used to co-evaporate the two compounds into one of the OLEDs through a vacuum thermal evaporation process. Emission layer.

Description

Organic electroluminescent material and device [Related applications]

This application claims 35 USC § 119 (e) U.S. Provisional Patent Application No. 61 / 940,603 filed on February 17, 2014, U.S. Provisional Patent Application No. 61 / 920,544 filed on December 24, 2013, US Provisional Patent Application No. 61 / 894,160 filed on October 22, 2013, US Provisional Patent Application No. 61 / 874,444 filed on September 6, 2013, and US Provisional Patent Application filed on August 20, 2013 No. 61 / 867,858 and No. 14 / 253,505 filed on April 15, 2014, the entirety of which are incorporated herein by reference.

[Parties of the Joint Research Agreement]

The claimed invention is made by one or more of the following parties who have reached a research agreement with United University Corporation, in the name of and / or in combination with one or more of the following parties Made by: University of Michigan Board of Governors, Princeton University, University of Southern California, and Universal Display Corporation. The agreement entered into force on and before the date of the claimed invention, and the claimed invention was made as a result of activities performed within the scope of the agreement.

The present invention relates to organic light emitting devices (OLEDs), and more particularly to organic materials used in such devices. More specifically, the present invention relates to a novel premix host system for phosphorescent OLEDs. At least one emitter and at least one other material are mixed in a vacuum thermal evaporation (VTE) process and co-evaporated from a sublimation crucible to achieve stable evaporation.

Optoelectronic devices using organic materials are becoming increasingly popular for several reasons. Many of the materials used to make such devices are relatively inexpensive, so organic optoelectronic devices have the potential to gain cost advantages over inorganic devices. In addition, the inherent properties of organic materials, such as their flexibility, can make them very suitable for specific applications, such as manufacturing on flexible substrates. Examples of organic optical electronic devices include organic light emitting devices (OLEDs), organic optoelectronic crystals, organic photovoltaic cells, and organic light detectors. For OLEDs, organic materials can have performance advantages over conventional materials. For example, the wavelength of light emitted by the organic emission layer can usually be easily adjusted with a suitable dopant.

OLEDs use organic thin films that emit light when a voltage is applied to the device. OLEDs are becoming an increasingly compelling technology for applications such as flat panel displays, lighting, and backlighting. Several OLED materials and configurations are described in US Patent Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.

One application of phosphorescent emitting molecules is full-color displays. The industry standard for such displays requires pixels that are suitable for emitting specific colors, called "saturated" colors. Specifically, these standards require saturated red, green, and blue pixels. Color can be measured using CIE coordinates, which are well known in the art.

An example of a green emitting molecule is tris (2-phenylpyridine) iridium, designated Ir (ppy) ₃ , which has the following structure:

In this figure and the figures later in this text, the coordination bonds from nitrogen to metal (here, Ir) are depicted as straight lines.

As used herein, the term "organic" includes polymeric materials as well as small molecule organic materials, which can be used to make organic optical electronic devices. "Small molecule" means any Organic materials, and "small molecules" may actually be quite large. In some cases, small molecules may include repeat units. For example, using a long-chain alkyl group as a substituent does not remove the molecule from the "small molecule" category. Small molecules can also be incorporated into polymers, for example as side groups on the polymer backbone or as part of the backbone. Small molecules can also act as the core of a dendrimer, which consists of a series of chemical shells built on the core. The core portion of the dendrimer can be a fluorescent or phosphorescent small molecule emitter. Dendrimers can be "small molecules", and all dendrimers currently used in the field of OLEDs are small molecules.

As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. In the case where the first layer is described as "positioned" on the second layer, the first layer is disposed farther from the substrate. Unless the first layer is required to "contact" the second layer, other layers may exist between the first and second layers. For example, even if there are various organic layers between the cathode and the anode, the cathode can still be described as "placed on" the anode.

As used herein, "solution processable" means capable of being dissolved, dispersed or transported in and / or deposited from a liquid medium in the form of a solution or suspension.

When the ligand is directly responsible for the photosensitivity of the emitting material, the ligand can be referred to as "photosensitive". When the Hamson ligand does not contribute to the photosensitivity of the emitting material, the ligand can be referred to as "auxiliary", but the auxiliary ligand can change the properties of the photoactive ligand.

As used herein, and as those skilled in the art will generally understand, if the first energy level is closer to the vacuum level, the first "highest occupied molecular orbital" (HOMO) or "lowest unoccupied molecular orbital" (LUMO) energy Level "greater than" or "greater than" the second HOMO or LUMO energy level. Since the ionization potential (IP) is measured as the negative energy relative to the vacuum level, a higher HOMO level corresponds to an IP with a smaller absolute value (a less negative IP). Similarly, higher LUMO energy levels correspond to electron affinity (EA) (less negative EA) with a smaller absolute value. In the conventional energy level diagram, the vacuum level is at the top, and the LUMO level of the material is higher than that of the same material. HOMO energy level. "Higher" HOMO or LUMO energy levels appear closer to the top of the graph than "lower" HOMO or LUMO energy levels.

As used herein, and as those skilled in the art will generally understand, if the first work function has a higher absolute value, the first work function is "greater than" or "higher" than the second work function. Because the work function is usually measured as a negative number relative to the vacuum level, this means that the "higher" work function is more negative. In the conventional energy level diagram, the vacuum level is at the top, and the "higher" work function is described as being farther away from the vacuum level in the downward direction. Therefore, the definition of the HOMO and LUMO energy levels follows a different convention than the work function.

Further details regarding OLEDs and the definitions described above can be found in US Patent No. 7,279,704, which is incorporated herein by reference in its entirety.

The invention provides a novel composition comprising a mixture of a first compound and a second compound, wherein the first compound has a chemical structure different from that of the second compound; wherein the first compound is capable of acting as an organic light-emitting device at room temperature. Phosphorescent emitter. The first compound may have an evaporation temperature T1 of 150 to 350 ° C. The second compound may have an evaporation temperature T2 of 150 to 350 ° C. To form a composition of the invention comprising a mixture of a first compound and a second compound, the absolute value of T1-T2, that is, the difference between T1 and T2 should be less than 20 ° C. The first compound in the mixture have a concentration of C1, and in the film have a concentration of C2, the membrane system by a vacuum deposition tool, ranges between 1 × 10 ^-6 Torr (Torr) to 1 × 10 ^{- At} a constant pressure of ⁹ Torr, the mixture is evaporated and deposited at a rate of 2 Å / sec on a surface placed at a predetermined distance from the positively evaporated mixture, and the absolute value of (C1-C2) / C1 is less than 5 %.

According to an embodiment of the present invention, a first device including a first organic light emitting device is disclosed. The first organic light emitting device includes: an anode; a cathode; and an organic layer disposed between the anode and the cathode, It comprises a first composition further comprising a mixture of a first compound and a second compound, wherein the first compound has a chemical structure different from that of the second compound; wherein the first compound is capable of acting as an organic light-emitting device at room temperature. Phosphorescent emitters in which the first compound has an evaporation temperature T1 of 150 to 350 ° C; wherein the second compound has an evaporation temperature T2 of 150 to 350 ° C; wherein the absolute value of T1-T2 is less than 20 ° C; wherein the first The concentration of a compound in the mixture is C1 and the concentration in the film is C2. The film is used in a vacuum deposition tool at a constant pressure between 1 × 10 ^-6 torr and 1 × 10 ^-9 torr. , The mixture is evaporated, and is deposited at a rate of 2 Å / sec on a surface placed at a predetermined distance from the mixture being evaporated, and the absolute value of (C1-C2) / C1 is less than 5%.

According to an embodiment of the present invention, a method for manufacturing an organic light emitting device is disclosed. The organic light emitting device includes a first electrode; a second electrode; and a first electrode disposed between the first electrode and the second electrode. An organic layer, wherein the first organic layer comprises a first organic composition further comprising a mixture of a first compound and a second compound. The method includes: providing a substrate having the first electrode disposed thereon; depositing the first composition on the first electrode; and depositing the second electrode on the first organic layer, wherein the first compound has Different from the chemical structure of the second compound; wherein the first compound is capable of acting as a phosphorescent emitter in an organic light-emitting device at room temperature; wherein the first compound has an evaporation temperature T1 of 150 to 350 ° C; wherein the second compound The compound has an evaporation temperature T2 of 150 to 350 ° C; wherein the absolute value of T1-T2 is less than 20 ° C; wherein the concentration of the first compound in the mixture is C1 and the concentration of the first compound in the film is C2. In a vacuum deposition tool, the mixture is evaporated at a constant pressure between 1 × 10 ^-6 torr and 1 × 10 ^-9 torr, and deposited at a rate of 2 Å / sec on the positively evaporated mixture and placed at a predetermined distance. And the absolute value of (C1-C2) / C1 is less than 5%.

100‧‧‧Organic light-emitting device

110‧‧‧ substrate

115‧‧‧Anode

120‧‧‧ Hole injection layer

125‧‧‧ Hole Transmission Layer

130‧‧‧ electron blocking layer

135‧‧‧Launching layer

140‧‧‧hole barrier

145‧‧‧ electron transmission layer

150‧‧‧ electron injection layer

155‧‧‧protective layer

160‧‧‧ cathode

162‧‧‧first conductive layer

164‧‧‧Second conductive layer

200‧‧‧OLED

210‧‧‧ substrate

215‧‧‧ cathode

220‧‧‧Layer

225‧‧‧ Hole Transmission Layer

230‧‧‧Anode

FIG. 1 illustrates an organic light emitting device that can incorporate the host material of the present invention disclosed herein.

FIG. 2 illustrates an inverted organic light emitting device that can incorporate the host material of the present invention disclosed herein.

Figures 3 (a) to 3 (c) show examples of white light OLEDs in top emission, bottom emission, and transparent OLED (TOLED) configurations.

4 (a) to 4 (d) show examples of blue-yellow white OLED structures.

5 (a) to 5 (g) show examples of two-cell white light stacked OLED structures.

6 (a) to 6 (c) show examples of white light stacked OLED structures having three or more units.

Generally, an OLED includes at least one organic layer disposed between an anode and a cathode and electrically connected to the anode and the cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer. The injected holes and electrons each migrate toward the oppositely charged electrode. When electrons and holes are confined to the same molecule, an "exciton" is formed, which is a localized electron-hole pair with an excited energy state. When an exciton relaxes via a light emission mechanism, light is emitted. In some cases, excitons can be limited to excimers or excitation complexes. Non-radiative mechanisms, such as thermal relaxation, can also occur, but are generally considered undesirable.

Original OLEDs used emitting molecules that emit light from a singlet ("fluorescence"), as disclosed, for example, in US Patent No. 4,769,292, which is incorporated by reference in its entirety. Fluorescent emission typically occurs in a time range of less than 10 nanoseconds.

Recently, OLEDs have been demonstrated with emissive materials that emit light from the triplet state ("phosphorescence"). "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices" by Baldo et al., Nature, vol. 395, pp. 151-154, 1998; ("Baldo-I") and "Very high-efficiency green organic light-emitting devices based on electrophosphorescence" by Baldo et al., Appl. Phys. Lett., Volume 75, Issue 3, pages 4-6 (1999) ("Baldo-II"), which is incorporated by reference in its entirety. Phosphorescence is described in more detail in US Patent No. 7,279,704, lines 5-6, incorporated by reference.

FIG. 1 illustrates an organic light emitting device 100. The figures are not necessarily drawn to scale. The device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transmission layer 125, an electron blocking layer 130, an emission layer 135, a hole blocking layer 140, an electron transmission layer 145, an electron injection layer 150, and a protective layer 155. , Cathode 160 and barrier layer 170. The cathode 160 is a composite cathode having a first conductive layer 162 and a second conductive layer 164. The device 100 may be manufactured by sequentially depositing the described layers. The properties and functions of these various layers and example materials are described in more detail in lines 6-10 of US 7,279,704, incorporated by reference.

There are more examples of each of these layers. For example, US Pat. No. 5,844,363, incorporated by reference in its entirety, discloses a flexible and transparent substrate-anode combination. An example of a p-doped hole transport layer is m-MTDATA doped with F ₄ -TCNQ at a molar ratio of 50: 1, such as US Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. Revealed in No. Examples of emitting materials and host materials are disclosed in US Patent No. 6,303,238, issued to Thompson et al., Which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1: 1, as disclosed in US Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, disclose examples of cathodes that include a thin metal layer such as Mg: Ag and an overlying transparent, conductive, sputter-deposited ITO layer Composite cathode. The principles and use of barrier layers are described in more detail in US Patent No. 6,097,147 and US Patent Application Publication No. 2003/0230980, which are incorporated by reference in their entirety. An example of an injection layer is provided in US Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety. A description of the protective layer can be found in US Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety.

Figure 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, an emission layer 220, a hole transmission layer 225, and an anode 230. The device 200 may be manufactured by sequentially depositing the described layers. Because the most common OLED configuration has a cathode placed on the anode and the device 200 has a cathode 215 placed under the anode 230, the device 200 may be referred to as an "inverted" OLED. In the corresponding layer of the device 200, materials similar to those described with respect to the device 100 may be used. FIG. 2 provides an example of how some layers may be omitted from the structure of the device 100.

The simple hierarchical structure illustrated in Figures 1 and 2 is provided as a non-limiting example, and it should be understood that embodiments of the present invention may be used in conjunction with a variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. Functional OLEDs can be implemented by combining the described layers in different ways based on design, performance, and cost factors, or several layers can be omitted entirely. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many of the examples provided herein describe various layers as containing a single material, it should be understood that a combination of materials (such as a mixture of a host and a dopant) or, more generally, a mixture may be used. And, the layers may have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in the device 200, the hole transmission layer 225 transmits a hole and injects the hole into the emission layer 220, and may be described as a hole transmission layer or a hole injection layer. In one embodiment, an OLED can be described as having an "organic layer" disposed between a cathode and an anode. This organic layer may include a single layer, or may further include multiple layers of different organic materials as described, for example, with respect to FIGS. 1 and 2.

Structures and materials not specifically described, such as OLEDs (PLEDs) containing polymeric materials, such as disclosed in U.S. Patent No. 5,247,190 issued to Friend et al., Incorporated by reference in its entirety, may also be used. As another example, a single organic layer can be used Of OLED. OLEDs can be stacked, for example, as described in US Patent No. 5,707,745, issued to Forrest et al., Which is incorporated by reference in its entirety. The OLED structure can be separated from the simple layered structure illustrated in FIGS. 1 and 2. For example, the substrate may include angled reflective surfaces to improve out-coupling, such as a mesa structure as described in U.S. Patent No. 6,091,195 issued to Forrest et al. The pit structure described in U.S. Patent No. 5,834,893 is incorporated by reference in its entirety.

Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, inkjet (such as described in U.S. Patent Nos. 6,013,982 and 6,087,196, incorporated by reference in their entirety), organic vapor deposition (OVPD) (such as Incorporated by way of U.S. Patent No. 6,337,102 to Forrest et al. And deposition by organic vapor jet printing (OVJP) (such as described in U.S. Patent No. 7,431,968, incorporated by reference in its entirety) . Other suitable deposition methods include spin coating and other solution-based methods. The solution-based method is preferably performed under a nitrogen or inert atmosphere. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding (such as described in U.S. Patent Nos. 6,294,398 and 6,468,819, which are incorporated by reference in their entirety) and with deposition methods such as inkjet and OVJD Some methods are associated with patterning. Other methods can also be used. The material to be deposited can be modified to make it compatible with a particular deposition method. For example, a branched or unbranched substituent such as an alkyl group and an aryl group may be used in small molecules to enhance its ability to withstand solution treatment. Substituents having 20 or more carbons may be used, with 3-20 carbons being a preferred range. Materials with asymmetric structures can have better solution processability than materials with symmetrical structures, because asymmetric materials can have a lower tendency to recrystallize. Dendrimer substituents can be used to enhance the ability of small molecules to withstand solution treatment.

The device manufactured according to the embodiment of the present invention may further include a barrier layer as appropriate. One use of the barrier layer is to protect the electrodes and organic layers from harmful substances due to exposure to the environment (Including moisture, vapor, and / or gas). The barrier layer can be deposited on the substrate, the electrode, under the substrate, the electrode, or beside the substrate, the electrode, or on any other part of the device (including the edge). The barrier layer may include a single layer or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques, and may include a composition having a single phase and a composition having a plurality of phases. Any suitable material or combination of materials can be used for the barrier layer. The barrier layer may incorporate an inorganic compound or an organic compound or both. Preferred barrier layers include a mixture of polymeric and non-polymeric materials, such as US Patent No. 7,968,146, PCT Patent Application Nos. PCT / US2007 / 023098, and PCT / US2009 / 042829, which are incorporated herein by reference in their entirety. As described. In order to be considered a "mixture," the aforementioned polymeric and non-polymeric materials constituting the barrier layer should be deposited under the same reaction conditions and / or at the same time. The weight ratio of the polymeric material to the non-polymeric material may be in the range of 95: 5 to 5:95. Polymeric and non-polymeric materials can be produced from the same precursor material. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric silicon and inorganic silicon.

Devices manufactured in accordance with embodiments of the present invention may be incorporated into a wide variety of consumer products, including flat panel displays, computer monitors, medical monitors, televisions, billboards, for internal or external lighting and / or Signalling lights, head-up displays, fully transparent displays, flexible displays, laser printers, telephones, mobile phones, personal digital assistants (PDAs), laptops, digital cameras, video cameras, viewfinders , Micro display, 3-D display, vehicle, large wall, theater or stadium screen, or signage. Various control mechanisms can be used to control devices made according to the present invention, including passive matrix and active matrix. Many of these devices are intended to be used in a temperature range comfortable for humans, such as 18 degrees Celsius to 30 degrees Celsius, and more preferably at room temperature (20-25 degrees Celsius), but can be outside this temperature range ( (Eg -40 degrees Celsius to +80 degrees Celsius).

The materials and structures described herein can be applied to devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic light detectors can make Use these materials and structures. More generally, organic devices such as organic transistors can use these materials and structures.

As used herein, the term "halo" or "halogen" includes fluorine, chlorine, bromine and iodine.

As used herein, the term "alkyl" encompasses both straight and branched chain alkyl groups. Preferred alkyl groups are alkyl groups containing one to fifteen carbon atoms, and include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl and the like. In addition, the alkyl group may be optionally substituted.

As used herein, the term "cycloalkyl" encompasses cyclic alkyl. Preferred cycloalkyls are cycloalkyls containing 3 to 7 carbon atoms, and include cyclopropyl, cyclopentyl, cyclohexyl and the like. In addition, the cycloalkyl group may be optionally substituted.

As used herein, the term "alkenyl" encompasses both straight and branched chain alkenyl groups. Preferred alkenyl groups are alkenyl groups containing two to fifteen carbon atoms. In addition, the alkenyl group may be optionally substituted.

As used herein, the term "alkynyl" encompasses both straight and branched chain alkynyl. Preferred alkyl groups are those containing two to fifteen carbon atoms. In addition, an alkynyl group may be substituted as appropriate.

As used herein, the terms "aralkyl" or "arylalkyl" are used interchangeably and encompass alkyl groups having an aromatic group as a substituent. In addition, the aralkyl group may be optionally substituted.

As used herein, the term "heterocyclyl" encompasses both aromatic and non-aromatic cyclic groups. Heteroaromatic cyclic groups are also referred to as heteroaryl. Preferred heteronon-aromatic cyclic groups are cyclic groups containing 3 or 7 ring atoms including at least one hetero atom, and include cyclic amines such as morpholinyl, piperidinyl, pyrrolidinyl and the like, And cyclic ethers, such as tetrahydrofuran, tetrahydropiperan, and the like. In addition, the heterocyclic group may be optionally substituted.

As used herein, the term "aryl" or "aromatic group" encompasses both monocyclic groups and polycyclic ring systems. A polycyclic ring may have two or more rings in which two carbons are two adjacent rings (the rings are "fused"), where at least one of the rings is aromatic. For example, other rings may Cycloalkyl, cycloalkenyl, aryl, heterocyclic and / or heteroaryl. In addition, the aryl group may be optionally substituted.

As used herein, the term "heteroaryl" encompasses monomers that may include one to three heteroatoms Ring heteroaromatic groups such as pyrrole, furan, thiophene, imidazole, oxazole, thiazole, triazole, pyrazole, pyridine, pyrazine, and pyrimidine and the like. The term heteroaryl also includes polycyclic heteroaromatic systems having two or more rings in which two atoms are shared by two adjacent rings (the rings are "fused"), wherein at least one of the rings This is a heteroaryl group. For example, the other ring may be a cycloalkyl group, a cycloalkenyl group, an aryl group, a heterocyclic ring, and / or a heteroaryl group. In addition, the heteroaryl group may be optionally substituted.

Alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclyl, aryl, and heteroaryl can be optionally substituted with one or more substituents selected from the group consisting of hydrogen, deuterium, Halogen, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, cyclic amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aromatic Group, heteroaryl group, fluorenyl group, carbonyl group, carboxylic acid group, ether group, ester group, nitrile group, isonitrile group, thio group, sulfinyl group, sulfonyl group, phosphine group, and combinations thereof.

As used herein, "substituted" means that a substituent other than H is bonded to the relevant position, such as carbon. Thus, for example, when R ¹ is monosubstituted, then one R ¹ must be other than H. Similarly, when R ¹ is disubstituted, then two R ¹ must not be H. Similarly, where R ¹ is unsubstituted, R ¹ is for all available positions are hydrogen.

The "aza" name in the fragments described in this document (i.e., aza-dibenzofuran, aza-dibenzothiophene, etc.) means that one or more CH groups in the respective fragments can be replaced by a nitrogen atom For example, and without any limitation, azabiphenylene includes dibenzo [ f, h ] quinoline and dibenzo [ f, h ] quinoline. One of ordinary skill can readily envision other nitrogen analogs of the aza-derivatives described above, and all such analogs are intended to be encompassed by terminology as set forth herein.

It should be understood that when a molecular fragment is described as a substituent or otherwise attached to another moiety, its name may be as if it were a fragment (e.g., naphthyl, dibenzofuranyl) or as if it were an entire molecule (such as (Furan) is generally written. As used herein, these different ways of naming substituents or linked fragments are considered equivalent.

In general, two types of emission layers (EML) are required for OLED devices that exhibit good lifetime and efficiency. The above components (for example, 3 or 4 components). The manufacture of such EMLs using a vacuum thermal evaporation (VTE) process then requires the evaporation of 3 or 4 evaporation source materials in separate VTE sublimation crucibles, as opposed to the standard two using a single body and emitter, which requires only two evaporation sources. Component EML is very complex and expensive.

Premixing two or more materials and evaporating them from a VTE sublimation crucible can reduce the complexity of the manufacturing process. However, co-evaporation must be stable and produce an evaporation film with a composition that remains constant during the evaporation process. Variations in the composition of the film may adversely affect device performance. In order to obtain stable co-evaporation from a mixture of compounds under vacuum, it is assumed that the materials must have the same evaporation temperature under the same conditions. However, this may not be the only parameter that must be considered. When two mixtures are mixed together, they may interact with each other and the evaporation characteristics of the mixture may differ from their individual characteristics. On the other hand, materials with slightly different evaporation temperatures may form stable co-evaporated mixtures. Therefore, obtaining a stable co-evaporated mixture is extremely difficult. To date, there are very few examples of stable co-evaporated mixtures. The "evaporation temperature" of a material is deposited in a vacuum deposition tool at a rate of 2 Å / sec under a constant pressure, usually between 1 × 10 ^-7 Torr and 1 × 10 ^-8 Torr, at a rate of 2 Å / sec. The evaporation source is measured on a surface placed at a certain distance. As one of ordinary skill in the art will appreciate, due to the expected tolerances of the measured values that produce these quantitative values, it is expected that each measured value such as temperature, pressure, deposition rate, etc. disclosed herein will have a nominal change.

Many non-temperature factors can help achieve the ability to stabilize co-evaporation, such as the miscibility of different materials and the phase transfer temperature of different materials. The inventors have discovered that when two materials have similar evaporation temperatures and similar mass loss rates or similar vapor pressures, the two materials can co-evaporate consistently. The "mass loss rate" of a material is defined as the percentage of mass loss over time ("percent / minute" or "% / min"), and, for example, after a stable evaporation state is reached, a given material is tested at a given constant temperature and in a given experiment Under the conditions, the time taken to measure the first 10% of the mass loss of the material sample is determined by thermogravimetric analysis (TGA) measurement. The constant temperature is one selected so that the value of the mass loss rate is between about 0.05 and 0.50% / min. Temperature point. Those familiar with this field should understand that in order to compare the two parameters, the experimental conditions should be the same. Methods for measuring mass loss rate and vapor pressure are well known in the art and can be found in, for example, Bull. Et al. Mater. Sci. 2011, 34, 7.

In the state of phosphorescent OLED device technology, EML can be composed of three or more components. In one example, EML can be composed of two host compounds and emitters (e.g., hole transport co-host (h-host), electron transport co-host (e-host), and phosphorescence in OLEDs at room temperature. Emitter compound). In another example, the EML may be composed of one host compound and two emitter compounds (eg, a host compound and two compounds each capable of acting as a phosphorescent emitter in an OLED at room temperature). Conventionally, in order to manufacture such an EML with three or more components using a VTE process, three or more evaporation sources are required, and one evaporation source is used for each component. Because component concentration is important for device performance, the deposition rate of each component is typically measured individually during the sedimentation process. This makes the VTE process complicated and expensive. Therefore, it is necessary to premix at least two of the components of such EML to reduce the number of VTE evaporation sources.

As used herein, "emitter-type compound" refers to a compound capable of acting as a phosphorescent emitter in an EML of an OLED at room temperature. "Host compound" refers to a compound capable of acting as a host material in an EML of an OLED at room temperature.

Premixing any two of three or more components in the EML and forming a mixture of stable co-evaporation sources will result in a reduction in the number of evaporation sources required for the EML layer. In order to premix the material as an evaporation source, it should be co-evaporated and deposited uniformly without changing the ratio. The ratio of the components in the mixture should be the same as the ratio of the components in the evaporated film formed from these premixed materials. Therefore, the concentration of the two components in the deposited film is controlled by their concentration in the premixed evaporation source.

This invention describes a novel type of emitter and another type of material (such as a host-type material) that can be premixed to provide a VTE co-evaporation source that can be used for stable co-evaporation of the two materials.

Maximizing the efficiency of a phosphorescent emitter in an OLED may include narrowing the emission spectrum. This side effect of narrow emission is not desirable in some applications, such as when the emitter is used as part of a white light emitting OLED. In applications such as white light emitting OLEDs, a broad full-width half-maximum (FWHM) spectrum is usually better.

One possible method to achieve high efficiency and wide FWHM spectrum is to incorporate two emitters in the device. This can be achieved by incorporating the emitters in separate EMLs or by depositing two emitters as one layer. The present inventors have discovered that by premixing two emitters with desired ratios with similar thermal evaporation characteristics and by using a VTE process to deposit these materials from an evaporation sublimation crucible containing mixed composition source materials, the materials can be deposited. This simplifies the manufacture of OLEDs with an EML containing two emitters.

The combination of premixed compounds described in the present invention (wherein at least one of the compounds is an emitter compound) can be used to fine-tune the device emission spectrum for a specific spectral width without compromising device efficiency. Premixing allows better control of the component ratio of the EML layer, thereby making the desired / obtained spectral shape more precise than when the components of the EML layer are evaporated from a separate evaporation source. This provides a more robust manufacturing process for OLEDs.

According to the present invention, the composition of a film deposited by vacuum thermal evaporation (VTE) from a premixed emitter evaporation source material is determined in advance in the mixing stage. The composition of the premixed emitter evaporation source material is determined by the desired contribution of the two emitter compounds used. The ratio of the two emitter compounds in the composition of the premix may be between 1: 1 and 200: 1. Preferably, the ratio is between 1: 1 and 50: 1, more preferably between 1: 1 and 20: 1, more preferably between 1: 1 and 5: 1 and most preferably between 1: 1 and 2: 1.

Examples

In a first example, two novel compound compounds with very similar sublimation characteristics, namely a novel combination of compound 20 and compound 145, were placed in a single deposition source and evaporated to a device EML with a variable ratio. For example, to make the film 2000Å thick, a mixture of these two emitters was deposited at 0.2Å / s. Material is then deposited on the substrate at a deposition rate of 1 Å / s On this, a 70 nm thick film was produced. The ratio of the two emitters in the premix was 85% (Compound 20) to 15% (Compound 145) as measured by weight before mixing. The composition of the premix was 84.5% (compound 20) to 15.5% (compound 145) as measured by high pressure liquid chromatography. Because mixing can cause inhomogeneities in the total premix, when analyzing small samples by HPLC, give a 1% error bar for the percentage measurement of the premix component. The composition of the deposited film was 85.3% (Compound 20) to 14.7% (Compound 145) as measured by HPLC. Therefore, the composition of the premix and the sedimentary material is comparable.

The novel combination of two compounds disclosed herein can be used to make a variety of white OLED configurations. For example, the two-compound mixture combination disclosed herein can be used to make a premixed emitter evaporation source material that can be used to deposit a wide yellow EML layer in a blue-yellow white OLED.

Examples of various configurations for such blue-yellow white OLEDs are illustrated in Figs. 3 (a) to 6 (c). The layers "Y EML", "Y1 EML", and "Y2 EML" in the picture are wide yellow EMLs and are well known in this technology. Wide yellow EML layers are usually composed of two emitter-type compounds in combination with blue EML layers. The desired emission spectrum required to produce white light. The layers "Ph B EML", "Fl B EML", "B EML", "B1 EML" and "B2 EML" in the figure are blue EML.

In these examples, the wide yellow EML layer is made of two emitter-type compounds to produce the desired light in the red-green, red-yellow, or yellow spectrum, and white light emission when combined with blue emission from the blue EML OLED. The premixed emitter evaporation source material disclosed herein is suitable for depositing such wide yellow EML layers by a VTE process.

Figures 3 (a) to 3 (c) show the basic configuration of a blue-yellow white OLED. FIG. 3 (a) shows an example of a blue-yellow white OLED (anode transparent) in a bottom emission configuration. Figure 3 (b) shows an example of a blue-yellow white OLED with a transparent OLED configuration (the anode and cathode are both transparent). FIG. 3 (c) shows an example of a blue-yellow white light OLED in a top emission configuration (cathode transparent). The examples shown in Figures 4 (a) to 6 (c) are all shown in the bottom launch configuration, but those skilled in the art will It will be understood that the examples shown in FIGS. 4 (a) to 6 (c) are equally applicable to top emission configurations and transparent OLED configurations.

4 (a) to 4 (d) show examples of a single-unit blue-yellow white OLED structure. 5 (a) to 5 (g) show examples of two-cell blue-yellow white light stacked OLED structures. 6 (a) to 6 (c) show examples of three-cell blue-yellow white light stacked OLED structures. Those skilled in the art will readily understand that these stacked OLED configurations are suitable for embodiments having more than three light emitting units. In these figures, the following abbreviations are used: HIL-hole injection layer, HTL-hole transport layer, EML-emission layer, ETL-electron transport layer, EIL-electron injection layer, SL-separation layer, CGL-charge generation Layer, Ph-phosphorescent, Fl-fluorescent. In these configurations, HIL2 can be the same material or different materials as HIL1, HTL3 can be the same material or different materials as HTL1, HTL4 can be the same material as HTL2 or different materials, and ETL3 can be the same material as ETL1 may be the same material or different materials, and ETL4 may be the same material or different materials as ETL2. B EML, B1 EML, and B2 EML are blue EMLs and they can be fluorescent or phosphorescent. B2 EML can be the same material as B1 EML or different materials. Y EML, Y1 EML, and Y2 EML are yellow EML and they may be fluorescent or phosphorescent. Y2 EML can be the same material as Y1 EML or different materials.

In the white light stack OLED structure of FIGS. 6 (a) to 6 (c), HIL2 may be the same material or different materials as HIL1, HTL3 may be the same material or different materials as HTL1, and HTL4 may be the same as HTL2 The materials may be different materials, ETL3 may be the same materials or different materials as ETL1, and ETL4 may be the same materials or different materials as ETL2. B EML1 and B EML2 represent blue EML and they may be fluorescent or phosphorescent. B EML1 may be the same material as B EML2 or a different material. Y EML stands for yellow EML. The number of stacked units may be any number greater than or equal to three. The number of blue and yellow EML units can be any number. The stacked units can be in any order, such as B / Y / B / Y or B / B / Y / Y, or B / Y / B / Y / B, etc., where B represents blue and Y represents wide yellow.

According to another aspect of the present invention, a second example of a premixed emitter evaporation source is disclosed. The premixed mixture according to this second example comprises an emitter compound, compound E5, and a host compound, compound H1. Compounds H1 and E5 exhibit premixability, meaning that they can be premixed and co-deposited from one evaporation source without changing composition. The consistency of the performance of the device manufactured by the premixed precursor thus requires uniform co-evaporation of the subject: the emitter pair. The structures of compound H1 and compound E5 are shown below:

The premixability of compound H1 and compound E5 was tested by HPLC analysis of the evaporated film. To this end, the host compound H1 (0.485 g) and the emitter compound E5 (0.015 g) were mixed and ground to form a 0.5 g mixture. The mixture was charged into an evaporation source in a vacuum VTE chamber. The suction chamber is reduced to a pressure of 10 ^-7 Torr. Premixed components were deposited on the glass substrate at a rate of 2 Å / s. Subsequent substrate replacement after deposition of 1100Å film without stopping deposition and cooling source. Evaporate the premixed material until it is consumed.

The deposited films were analyzed by HPLC (HPLC conditions C18, 80-100 (CH ₃ CN concentration in CH ₃ CN and H ₂ O), 30 min, detection wavelength 254 nm), and the results are shown in Table 1 below. The composition of the host compound H1 and the emitter compound E5 did not change significantly from plate 1 to plate 3. Each of the sample substrates is labeled Plate 1, Plate 2, and Plate 3. Certain fluctuations in concentration do not reveal any trends and can be explained by the accuracy of the HPLC analysis.

This data shows that host compound H1 and emitter compound E5, and other hosts and emitters from these families that may be present, can be premixed to be used as a single evaporation source for EML or partial EML of PHOLED.

Examples of other possible premixed bodies: emitter pairs are provided in Table 2 below.

The host compound EH40 and the emitter compound 97 also exhibit premixability. This means that it can be premixed and co-deposited from one source without changing composition. Uniform co-evaporation of the body: The emitter is critical to the consistency of the performance of the device made from this premixed precursor. The structures of the host compound EH40 and the emitter compound 97 are shown below.

The premixability of compound EH40 and compound 97 was tested by HPLC analysis of the evaporated film. To this end, the host compound EH40 and the emitter compound 97 were mixed at a ratio of about 7: 1 and ground to form a 0.2 g mixture. The mixture was charged into an evaporation source in a vacuum VTE chamber. The suction chamber is reduced to a pressure of 10 ^-7 Torr. Premixed components were deposited on the glass substrate at a rate of 2 Å / s. Subsequent substrate replacement after depositing 500Å film without stopping deposition and cooling source. Evaporate the premixed material until it is consumed.

By HPLC (HPLC conditions C18,100% CH ₃ CN, 30min, detection wavelength 254 nm) Analysis of the film, and the results are shown in Table 3. The composition of the host compound EH40 and the emitter compound 97 did not change significantly from plate 1 to plate 5. Each of the sample substrates is labeled Plate 1, Plate 2, Plate 3, Plate 4, and Plate 5. Certain fluctuations in concentration do not reveal any trends and can be explained by the accuracy of the HPLC analysis.

This is evidence that the host compound EH40 and the emitter compound 97, and other hosts and emitters from these families that may be present, can be premixed for use as a single evaporation source for the EML or partial EML of a PHOLED. Examples of other possible premixed bodies: emitter pairs are provided in Table 4 below.

According to one aspect of the invention, a composition comprising a mixture of a first compound and a second compound is now described. In the mixture, the first compound has a chemical structure different from that of the second compound. The first compound is capable of acting as a phosphorescent emitter in an OLED at room temperature. The first compound has an evaporation temperature T1 of 150 to 350 ° C and the second compound has The evaporation temperature T2 of 150 to 350 ° C, wherein the absolute value of T1-T2, that is, the difference between T1 and T2 is less than 20 ° C. Preferably, the absolute value of T1-T2 is less than 10 ° C and more preferably less than 5 ° C.

The concentration of the first compound in the mixture is C1, and the concentration in the film is C2. The film is formed in a vacuum deposition tool at a temperature between 1 × 10 ^-6 Torr and 1 × 10 ^-9 Torr. Under constant pressure, the mixture is evaporated and deposited at a rate of 2 Å / sec on a surface placed at a predetermined distance from the evaporation source of the positively evaporated mixture, and the absolute value of (C1-C2) / C1 is less than 5 %. Preferably, the absolute value of (C1-C2) / C1 is less than 3%.

The concentrations C1 and C2 are relative concentrations of the first compound. Therefore, the requirements for the two compounds forming the above-mentioned mixture mean that the relative concentration (C2) of the first compound in the deposited state film should be as close as possible to the original relative concentration (C1) of the first compound in the evaporation source mixture. Those of ordinary skill in the art will recognize that the concentration of each component in the mixture is expressed as a relative percentage. The concentration of each component in the mixture can be measured by suitable analytical methods familiar to those skilled in the art. Examples of such methods are high pressure liquid chromatography (HPLC) and nuclear magnetic resonance spectroscopy (NMR). The percentage is calculated by dividing the integrated area under the HPLC trace of each component by the total integrated area. HPLC can use different detectors, such as UV-visible, photodiode array detectors, refractive index detectors, fluorescence detectors, and light scattering detectors. Due to different material properties, each component in the mixture may respond differently. Therefore, the measured concentration may be different from its true concentration in the mixture. However, as long as the experimental conditions remain constant, the relative ratio of (C1-C2) / C1 is independent of these variables. For example, each component should be exactly the same All concentrations were calculated under HPLC parameters. It is sometimes preferable to select measurement conditions that produce a calculated concentration that is close to the true concentration. However, it is not necessary. It is important to choose detection conditions that accurately detect each component. For example, if one of the components does not fluoresce, a fluorescence detector should not be used.

In one embodiment, the first compound has an evaporation temperature T1 of 200 to 350 ° C and the second compound has an evaporation temperature T2 of 200 to 350 ° C.

In one embodiment, the vapor pressure of the first compound at 1 atm under T1 is P1, and The vapor pressure of the second compound at 1 atm under T2 is P2. The ratio of P1 / P2 is desirably in the range of 0.90 to 1.10.

The first compound has a first mass loss rate and the second compound has a second mass loss rate, wherein a ratio between the first mass loss rate and the second mass loss rate is desirably in a range of 0.90 to 1.10. Preferably, a ratio between the first mass loss rate and the second mass loss rate is in a range of 0.95 to 1.05. More preferably, a ratio between the first mass loss rate and the second mass loss rate is in a range of 0.97 to 1.03.

The phosphorescent emitter component in the composition is capable of emitting light from a triplet excited state to a singlet ground state at room temperature. In one embodiment of the composition, the first compound is a metal coordination complex having a metal-carbon bond. The metal in the metal-carbon bond may be selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu. In another embodiment, the metal is Ir (iridium). In another embodiment, the metal is Pt (platinum).

In one embodiment of the composition, the second compound is capable of acting as a phosphorescent emitter in an OLED at room temperature.

In another embodiment, the second compound is capable of acting as a host in the EML of the OLED at room temperature. In one embodiment, the body is a hole transmission body. In another embodiment, the subject is an electronic transmission subject.

According to one aspect of the present invention, the lowest triplet energy TE1 of the first compound is lower than the lowest triplet energy of the second compound. The triplet energy is determined by phosphorescence in an organic solvent glass at 77 ° K.

In one embodiment of the composition, the second compound comprises at least one chemical group selected from the group consisting of: triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenphene, nitrogen Hetero-biphenylene, aza-carbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.

In one embodiment of the composition, the first compound and the second compound each have a purity of more than 99% as determined by HPLC.

According to another aspect, the mixture in the composition further comprises a third compound. The third compound has a chemical structure different from the first compound and the second compound, wherein the third compound has an evaporation temperature T3 of 150 to 350 ° C; and wherein the absolute value of T1-T3 is less than 20 ° C. Preferably, the absolute value of T1-T3 is less than 10 ° C, and more preferably less than 5 ° C.

In one embodiment, the composition is liquid at temperatures less than T1 (the evaporation temperature of the first compound) and T2 (the evaporation temperature of the second compound).

In one embodiment of the composition, the first compound has the formula M (L ¹ ) _x (L ² ) _y (L ³ ) _z ; wherein L ¹ , L ² and L ³ may be the same or different; wherein x is 1, 2 or 3; wherein y is 0, 1 or 2; wherein z is 0, 1 or 2; wherein x + y + z is the oxidation state of metal M; wherein L ¹ , L ² and L ³ are independently selected from the following Groups of formation: Wherein R _a, R _b, R _c and R _d may represent a mono-, di-, tri- or tetra-substituted or unsubstituted; wherein R _a, R _b, R _c and R _d line is independently selected from the group consisting of the group: Hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl , Aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, phosphine, and combinations thereof; and wherein R _a , Two adjacent substituents of R _b , R _c and _Rd are optionally joined to form a fused ring or to form a multidentate ligand.

According to another embodiment, wherein the first compound has the formula M (L ¹ ) _x (L ² ) _y (L ³ ) _z as defined above, the first compound has the formula Ir (L ¹ ) ₂ (L ² ).

In one embodiment, wherein the first compound has the formula Ir (L ¹ ) ₂ (L ² ), and L ² has the following formula: Wherein R _e, R _f, R _h and R _i are independently selected from the system consisting of the group consisting of: alkyl, cycloalkyl, aryl and heteroaryl; wherein R _e, R _f, R _h, and R _i in the At least one has at least two carbon atoms; wherein R _g is selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy Base, amine, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio , Sulfenyl, sulfofluorenyl, phosphino, and combinations thereof.

In one embodiment, wherein the first compound has the formula Ir (L ¹ ) ₂ (L ² ), and L ² has a formula selected from the group consisting of:

In another embodiment, wherein the first compound has the formula M (L ¹ ) _x (L ² ) _y (L ³ ) _z as defined above, the first compound has the formula Pt (L ¹ ) ₂ or Pt (L ¹ ) (L ² ). L ¹ may be linked to another L ¹ or L ² to form a tetradentate ligand.

In one embodiment of the composition, the first compound has formula I: Wherein R ^A represents a single, two, three, four, five, or six substituents or no substituents; R ^B represents a single, two, three, four, or four substituents; R ^A , R ^B , R ^C , R ^D And R ^E are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, and cyclic amino , Silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, thio, Sulfinyl, sulfonyl, phosphino and combinations thereof; wherein n is 1 or 2; wherein the second compound has formula II: Wherein R ¹ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine Group, cyclic amino group, silyl group, alkenyl group, cycloalkenyl group, heteroalkenyl group, alkynyl group, aryl group, heteroaryl group, fluorenyl group, carbonyl group, carboxylic acid group, ether group, ester group, nitrile group, isonitrile Group, thio group, sulfinyl sulfenyl group, sulfofluorenyl group, phosphinyl group, and combinations thereof; wherein L is selected from the group consisting of direct bond, aryl group, substituted aryl group, heteroaryl group, substituted heteroaryl group And combinations thereof; wherein X ¹ , X ² , X ³ , X ⁴ , X ⁵ , X ⁶ , X ⁷ , Y ¹ , Y ² and Y ³ are each independently selected from the group consisting of CR and N; wherein Y ¹ And at least two of Y ² and Y ³ are N; and each of R may be the same or different, and is independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, and heteroalkane Aryl, aralkyl, alkoxy, aryloxy, amine, cyclic amine, silane, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, Carboxylic acid group, ether group, ester group, nitrile group, isonitrile , Thio, sulfinyl group, acyl sulfo, phosphino, and combinations thereof.

In another embodiment, R ¹ , R ⁴ and R ⁵ in Formula II are independently selected from the group consisting of: non-fused aryl, non-fused heteroaryl, and combinations thereof; wherein L is selected from the group consisting of A group consisting of a direct bond, a non-fused aryl group, a non-fused heteroaryl group, and a combination thereof; and wherein each of R is independently selected from the group consisting of hydrogen, deuterium, non-fused aryl group, Non-fused heteroaryl and combinations thereof.

In another embodiment, R ¹ in Formula II is selected from the group consisting of phenyl, biphenyl, bitriphenyl, tetraphenyl, pentaphenyl, pyridine, phenylpyridine, and pyridylbenzene. base.

In another embodiment, L in Formula II is selected from the group consisting of phenyl, pyridyl, biphenyl, bitriphenyl, and direct bonds.

In another embodiment, R ⁴ and R ⁵ in Formula II are each independently selected from the group consisting of phenyl, pyridyl, biphenyl, and bitriphenyl.

In another embodiment of the composition, wherein the first compound has a structure according to Formula I as defined above, and the second compound has a structure according to Formula III: Wherein R ² and R ³ are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, Cycloamino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, Thio, sulfenamido, sulfoamido, phosphino, and combinations thereof.

In one embodiment, R ² and R ³ in Formula III are each independently selected from the group consisting of hydrogen, deuterium, non-fused aryl, non-fused heteroaryl, and combinations thereof.

In one embodiment, wherein the second compound has a structure of Formula III, the second compound may have a structure selected from the group consisting of:

In one embodiment of the composition, wherein the first compound has a structure of Formula I, n is 1. In another embodiment, R ^A , R ^B , R ^C , R ^D and ^RE are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof. In another embodiment, at least one of R ^C and R ^E contains a branched alkyl moiety having branches at positions further from the alpha position of the carbonyl group. In another embodiment, R ^D is hydrogen.

In one embodiment of the composition, wherein the first compound has a structure of Formula I, at least one of R ^C and R ^E has the following structure: Wherein R ^F and R ^G are independently selected from the group consisting of: alkyl and cycloalkyl; and wherein at least one of R ^F and R ^G has at least two C's.

In one embodiment of the composition, wherein the second compound has a structure according to Formula II as defined above, and the first compound has a structure according to Formula IV: Wherein R ^H and R ^J are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, Cycloamino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, Thio, sulfenamido, sulfoamido, phosphino, and combinations thereof.

In another embodiment of the composition, wherein the first compound has a structure according to formula IV as defined above, R ^H and R ^J are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl And combinations.

In another embodiment of the composition, wherein the first compound has a structure according to formula IV as defined above, and R ^H and R ^J are methyl.

In one embodiment of the composition, wherein the second compound has a structure according to Formula II, the second compound may be selected from the group consisting of:

In another embodiment of the composition, wherein the first compound has a structure according to formula I as defined above, the first compound may be selected from the group consisting of:

In another embodiment of the composition, wherein the first compound has a structure according to Formula I as defined above and the second compound has a structure according to Formula II, the mixture of the first compound and the second compound is selected from the group consisting of Groups: (Compound E5 and Compound H1), (Compound E1 and Compound H14), (Compound E4 and Compound H21), (Compound E9 and Compound H30), (compound E17 and compound H21), and (compound E13 and compound H33).

In another embodiment of the composition, wherein the first compound has a structure according to Formula I as defined above and the second compound has a structure according to Formula II, the mixture of the first compound and the second compound is (Compound E5 and Compound H1).

In an embodiment of a composition comprising a mixture of a first compound and a second compound, wherein the first compound has a chemical structure different from that of the second compound, wherein the first compound is capable of functioning as an OLED in an OLED at room temperature. The phosphorescent emitter, the first compound and the second compound each independently have a formula Ir (L ¹ ) ₂ (L ² ), where L ¹ has the following formula: Where L ² has the following formula: Where L ^{1 is} different from L ² ; where _Raa , _Rbb , _Rcc, and _Rdd can represent mono-, di-, tri-, or tetra-substituent or unsubstituted; where _Raaa , _Rbb , _Rcc, and _Rdd are independent Ground is selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloolefin Group, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, sulfonyl, phosphino, and A combination thereof; wherein two adjacent substituents of R _aa , R _bb , R _cc, and R _dd are optionally joined to form a fused ring or form a polydentate ligand; and wherein at least one of R _cc is 5 Or 6-membered carbocyclic or heterocyclic ring.

In one embodiment of the composition, wherein the first compound and the second compound each independently have the formula Ir (L ¹ ) ₂ (L ² ) as defined above, at least one of R _cc is benzene or pyridine.

In one embodiment of the composition, wherein the first compound and the second compound each independently have the formula Ir (L ¹ ) ₂ (L ² ) as defined above, L ¹ is selected from the group consisting of:

In one embodiment of the composition, the first compound and the second compound each independently have the formula Ir (L ¹ ) ₂ (L ² ) as defined above, and L ² is selected from the group consisting of:

In one embodiment of the composition, wherein the first compound and the second compound each independently have the formula Ir (L ¹ ) ₂ (L ² ) as defined above, the first compound and the second compound are each independently selected from the group consisting of The following groups:

In one embodiment of the composition, wherein the first compound and the second compound each independently have the formula Ir (L ¹ ) ₂ (L ² ) as defined above, the mixture of the first compound and the second compound is selected from the group consisting of A group consisting of (Compound 7 and Compound 130), (Compound 8 and Compound 131), (Compound 25 and Compound 131), (Compound 27 and Compound 135), (Compound 20 and Compound 145), (Compound 25 and Compound 148), (Compound 40 and Compound 174), (Compound 103 and Compound 204), and (Compound 116 and Compound 217).

In one embodiment of a composition comprising a mixture of a first compound and a second compound, wherein the first compound has a chemical structure different from that of the second compound, wherein the first compound is capable of acting as an OLED in an OLED at room temperature. Phosphorescent emitter, the first compound has a structure according to Formula V: Wherein R ¹¹ and R ¹² each independently represent a mono-, di-, tri-, or tetra-substituent or an unsubstituted group; Y is selected from the group consisting of: O, S, Se, NR 'and CR "R'''; L ¹ is a single bond or contains an aryl or heteroaryl group optionally having 5 to 24 carbon atoms, optionally further substituted; Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ are each independently selected from CR ′ A group consisting of '''andN; at least one of Z ¹ , Z ² , Z ³ , Z ^4, and Z ⁵ is N; and R ¹¹ , R ¹² , R', R ", R ''', and R '''' Are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silane , Alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfenyl, sulfo Fluorenyl, phosphino, and combinations thereof; wherein the second compound has formula VI: Wherein R ^AA , R ^BB , R ^DD and R ^EE each independently represent a mono, di, tri, or tetra substituent or no substituent; R ^CC represents a mono, di, tri, or unsubstituted substituent; R ^AA , R ^BB , R ^CC , R ^DD and R ^EE are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, Amine, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfenyl Sulfofluorenyl, sulfofluorenyl, phosphino, and combinations thereof; and m is 1 or 2.

In one embodiment, wherein the second compound has a structure according to Formula II as defined above, of the, X ^1, X ³ and X ⁵ is N; and X ² and X ⁴ is CR ''''.

In one embodiment, wherein the second compound has a structure according to Formula VI, m is 1. In another embodiment, R ^AA , R ^BB , R ^CC and R ^DD are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof. In another embodiment, R ^EE is selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, and combinations thereof.

In another embodiment, wherein the second compound has a structure according to formula VI as defined above, the second compound is selected from the group consisting of:

In another embodiment, wherein the first compound has a structure according to formula V as defined above, the first compound is selected from the group consisting of:

In one embodiment of the composition, wherein the second compound has a structure according to Formula VI, the second compound is selected from the group consisting of:

In one embodiment of the composition, wherein the first compound has a basis as defined above The structure of formula V and the second compound has a structure according to formula VI. The mixture of the first compound and the second compound is selected from the group consisting of: (compound EH1 and compound 4), (compound EH2 and compound 7), (Compound EH4 and compound 3), (compound EH5 and compound 11), (compound EH8 and compound 1), (compound EH8 and compound 67), (compound EH16 and compound 21), (compound EH28 and compound 29), (compound EH40 and compound 34) and (compound EH40 and compound 97).

In another embodiment of the composition, wherein the first compound has a structure according to Formula V and the second compound has a structure according to Formula VI, a mixture of the first compound and the second compound is (Compound EH40 and Compound 97).

According to another aspect of the present invention, a first device including a first OLED is disclosed. The first OLED includes: an anode; a cathode; and an organic layer disposed between the anode and the cathode, which includes a first composition containing a mixture of a first compound and a second compound, wherein the first compound has a different The chemical structure of the second compound; wherein the first compound is capable of acting as a phosphorescent emitter in an organic light-emitting device at room temperature; wherein the first compound has an evaporation temperature T1 of 150 to 350 ° C .; wherein the second compound has 150 Evaporation temperature T2 to 350 ° C; wherein the absolute value of T1-T2 is less than 20 ° C; wherein the concentration of the first compound in the mixture is C1, and the concentration of the first compound is C2. In a vacuum deposition tool, the mixture is evaporated at a constant pressure between 1 × 10 ^-6 Torr and 1 × 10 ^-9 Torr, and deposited at a rate of 2 Å / sec on a surface placed at a predetermined distance from the material. Form; and where the absolute value of (C1-C2) / C1 is less than 5%. Preferably, the absolute value of (C1-C2) / C1 is less than 3%.

In one embodiment of the first device, the organic layer is an emission layer. On the other device In one embodiment, the organic layer is a non-emissive layer.

In one embodiment of the first device, the organic layer further comprises a phosphorescent emitting material.

In one embodiment of the first device, the organic layer further includes a host.

In one embodiment of the first device, the first compound acts as a phosphorescent emitting material.

In one embodiment of the first device, the first compound serves as a host.

In one embodiment of the first device, the first device further includes a second organic light emitting device separate from the first organic light emitting device, and wherein the second organic light emitting device includes a peak wavelength between 400 nm and 500 nm. Its emitting dopant.

In one embodiment of the first device, the first organic light emitting device includes a first emission layer and a second emission layer; wherein the first emission layer includes a first composition; and the second emission layer includes a peak wavelength between 400 and 400. Emission dopants from nanometers to 500 nanometers.

In one embodiment of the first device, the first device is a consumer product. In another embodiment, the first device is an organic light emitting device. In another embodiment, the first device is a lighting board.

In one embodiment of the first device, after the first composition is consumed in the evaporation process, the first composition leaves a residue corresponding to less than 5 wt% of the original feed in the sublimation crucible. Preferably, the first composition is deposited in a vacuum system having a pressure level in the range of 1 × 10 ^-8 Torr to 1 × 10 ^-12 Torr.

According to another aspect of the present invention, a method for manufacturing an organic light emitting device is disclosed. The organic light emitting device includes a first electrode; a second electrode; and a first organic layer disposed between the first electrode and the second electrode. The first organic layer includes a first composition containing a mixture of a first compound and a second compound. The method includes the steps of: providing a substrate having the first electrode disposed thereon; depositing the first composition on the first electrode; and depositing the second electrode on the first organic layer, wherein the first electrode The compound has a chemical structure different from the second compound, wherein the first compound is capable of acting as a phosphorescent emitter in an organic light-emitting device at room temperature, wherein the first compound has an evaporation temperature T1 of 150 to 350 ° C., wherein the first compound The two compounds have an evaporation temperature T2 of 150 to 350 ° C, wherein the absolute value of T1-T2 is less than 20 ° C, wherein the concentration of the first compound in the mixture is C1, and the concentration of the first compound is C2, the film system The mixture was evaporated in a vacuum deposition tool at a constant pressure between 1 × 10 ^-6 Torr and 1 × 10 ^-9 Torr, and deposited at a predetermined distance from the material at a rate of 2 Å / sec. It is formed on the surface, and the absolute value of (C1-C2) / C1 is less than 5%.

Combination with other materials

Materials described herein as being useful for a particular layer in an organic light emitting device can be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a variety of hosts, transport layers, barrier layers, implant layers, electrodes, and other layers that may exist. The materials described or mentioned below are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

HIL / HTL:

The hole injection / transmission material used in the present invention is not particularly limited, and any compound can be used as long as the compound is typically used as a hole injection / transmission material. Examples of such materials include, but are not limited to: phthalocyanine or porphyrin derivatives; aromatic amine derivatives; indolocarbazole derivatives; polymers containing fluorocarbons; polymers with conductive dopants; conductive polymers, such as PEDOT / PSS; self-assembling monomers derived from phosphonic acid compounds and derivatives of such as silicon; a metal-oxide derivatives, such as MoO _x; p-type organic semiconductor, such as 1,4,5,8 , 9,12-Hexazatriphenyltriphenylhexanitrile; metal complexes, and crosslinkable compounds.

Examples of aromatic amine derivatives used in HIL or HTL include, but are not limited to, the following general structure:

Each of Ar ¹ to Ar ⁹ is selected from the group consisting of aromatic hydrocarbon ring compounds such as benzene, biphenyl, bitriphenyl, diphenyltriphenyl, naphthalene, anthracene, fluorene, phenanthrene, pyrene, fluorene , , Pyrene, pyrene; a group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzo Selenophene, carbazole, indolocarbazole, pyridylindole, pyrrolobipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole , Pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoloxazine, benzoxazole, benzoxazine Azole, benzothiazole, quinoline, isoquinoline, Phthaloline, quinazoline, quinololine, naphthyridine, phthalazine, pyridine, dibenzopiperan, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furobipyridine, Benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophendipyridine; and a group consisting of 2 to 10 cyclic structural units selected from aromatic hydrocarbon ring groups And aromatic heterocyclic groups of the same type or different types, and directly or via at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group Are bonded to each other. Wherein each Ar is further substituted with a substituent selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, Silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfenyl , Sulfofluorenyl, phosphino, and combinations thereof.

In one aspect, Ar ¹ to Ar ^{9 are} independently selected from the group consisting of:

Where k is an integer from 1 to 20; X ¹⁰¹ to X ¹⁰⁸ are C (including CH) or N; Z ¹⁰¹ is NAr ¹ , O, or S; Ar ¹ has the same group as defined above.

Examples of metal complexes used in HIL or HTL include, but are not limited to, the following general formula:

Where Met is a metal, which may have an atomic weight greater than 40; (Y ¹⁰¹ -Y ¹⁰² ) is a bidentate ligand, Y ¹⁰¹ and Y ^{102 are} independently selected from C, N, O, P, and S; L ¹⁰¹ is an auxiliary Ligands; k 'is an integer value from 1 to the maximum number of ligands that can be attached to a metal; and k' + k "is the maximum number of ligands that can be attached to a metal.

In one aspect, (Y ¹⁰¹ -Y ¹⁰² ) is a 2-phenylpyridine derivative.

In another aspect, (Y ¹⁰¹ -Y ¹⁰² ) is a carbene ligand.

In another aspect, Met is selected from Ir, Pt, Os, and Zn.

In another aspect, the metal complex has a solution state minimum oxidation potential relative to the Fc ⁺ / Fc pair of less than about 0.6V.

main body:

The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as a light-emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound can be used as long as the triplet energy of the host is greater than the triplet energy of the dopant. Although the table below categorizes the host materials that are preferred for devices that emit various colors, any host The material can be used with any dopant as long as the triplet criterion is met.

Examples of metal complexes used as the host preferably have the following general formula:

Where Met is a metal; (Y ¹⁰³ -Y ¹⁰⁴ ) is a bidentate ligand, Y ¹⁰³ and Y ^{104 are} independently selected from C, N, O, P, and S; L ¹⁰¹ is another ligand; k 'is An integer from 1 to the maximum number of ligands that can be linked to a metal; and k '+ k "is the maximum number of ligands that can be linked to a metal.

In one aspect, the metal complex is:

Among them, (O-N) is a bidentate ligand having a metal coordinated with O and N atoms.

In another aspect, Met is selected from Ir and Pt.

In another aspect, (Y ¹⁰³ -Y ¹⁰⁴ ) is a carbene ligand.

Examples of the organic compound used as the host are selected from the group consisting of aromatic hydrocarbon ring compounds such as benzene, biphenyl, bitriphenyl, diphenyltriphenyl, naphthalene, anthracene, fluorene, phenanthrene, pyrene, pyrene, , Pyrene, pyrene; a group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzo Selenophene, carbazole, indolocarbazole, pyridylindole, pyrrolobipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole , Pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoloxazine, benzoxazole, benzoxazine Azole, benzothiazole, quinoline, isoquinoline, Phthaloline, quinazoline, quinololine, naphthyridine, phthalazine, pyridine, dibenzopiperan, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furobipyridine, Benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophendipyridine; and a group consisting of 2 to 10 cyclic structural units selected from aromatic hydrocarbon ring groups And aromatic heterocyclic groups of the same type or different types, and directly or via at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group Are bonded to each other. Wherein each group is further substituted with a substituent selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine , Silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfenyl Group, sulfofluorenyl group, phosphino group and combinations thereof.

In one aspect, the host compound contains at least one of the following groups in the molecule:

Wherein R ¹⁰¹ to R ^{107 are} independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, silane , Alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfenyl, sulfo The fluorenyl, phosphino, and combinations thereof, when they are aryl or heteroaryl, have similar definitions as Ar.

k is an integer from 0 to 20 or 1 to 20; k '"is an integer from 0 to 20.

X ¹⁰¹ to X ^{108 are} selected from C (including CH) or N.

Z ¹⁰¹ and Z ^{102 are} selected from NR ¹⁰¹ , O, or S.

HBL:

A hole blocking layer (HBL) can be used to reduce the number of holes and / or excitons leaving the emitting layer. The presence of such a barrier layer in a device can produce substantially higher efficiencies than similar devices lacking a barrier layer. In addition, a barrier layer can be used to limit emission to a desired area of the OLED.

In one aspect, the compound used in the HBL contains the same molecule or the same functional group as the above host.

In another aspect, the compound used in HBL contains at least one of the following groups in the molecule:

Where k is an integer from 1 to 20; L ¹⁰¹ is another ligand, and k 'is an integer from 1 to 3.

ETL:

The electron transport layer (ETL) may include materials capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or doped. Doping can be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complex or organic compound can be used as long as it is typically used to transport electrons.

In one aspect, the compound used in the ETL contains at least one of the following groups in the molecule:

Wherein R ^{101 is} selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, and cyclo Alkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulfinyl, sulfonyl, sulfonyl, phosphine And its combination, when it is an aryl or heteroaryl group, it has a similar definition to Ar.

Ar ¹ to Ar ³ have similar definitions as Ar described above.

k is an integer from 1 to 20.

X ¹⁰¹ to X ^{108 are} selected from C (including CH) or N.

In another aspect, the metal complex used in the ETL contains (but is not limited to) the following general formula:

Where (ON) or (NN) is a bidentate ligand with a metal coordinated to the atom O, N or N, N; L ¹⁰¹ is another ligand; k 'is 1 to the maximum that can be connected to the metal An integer value for the number of ligands.

In any of the aforementioned compounds used in each layer of the OLED device, the hydrogen atom may be partially or fully deuterated. Thus, any specifically listed substituents (such as, but not limited to, methyl, phenyl, pyridyl, etc.) encompass their non-deuterated, partially deuterated, and fully deuterated forms. Similarly, substituent classes (such as, but not limited to, alkyl, aryl, cycloalkyl, heteroaryl, etc.) also encompass their non-deuterated, partially deuterated, and fully deuterated forms.

In addition to and / or in combination with the materials disclosed herein, many hole injection materials, hole transport materials, host materials, dopant materials, exciton / hole barrier materials can be used in OLEDs , Electron transmission materials and electron injection materials. Non-limiting examples of materials that can be used in combination with the materials disclosed herein for OLEDs are listed in Table 5 below. Table 5 lists non-limiting categories of materials, non-limiting examples of compounds in each category, and references that disclose such materials.

table 5

It should be understood that the various embodiments described herein are examples only and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein can be replaced with other materials and structures without departing from the spirit of the invention. The invention as claimed may therefore include variations from the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It should be understood that various theories as to why the invention works are not intended to be limiting.

Claims (9)

A composition comprising a mixture of a first compound and a second compound; wherein the first compound has a chemical structure different from that of the second compound; wherein the first compound is capable of acting as phosphorescent emission in an organic light emitting device at room temperature Wherein the first compound has an evaporation temperature T1 of 150 to 350 ° C; wherein the second compound has an evaporation temperature T2 of 150 to 350 ° C; wherein the absolute value of T1-T2 is less than 20 ° C; wherein the first compound is in the The concentration in the mixture is C1 and the concentration in a film is C2. The film is deposited in a vacuum deposition tool between 1 × 10 ^-6 Torr and 1 × 10 ^-9 Torr. Under constant pressure, the mixture is evaporated and deposited at a rate of 2 Å / sec on a surface placed at a predetermined distance from the evaporated mixture, where the absolute value of (C1-C2) / C1 is less than 5%, Wherein the first compound has a structure according to Formula I: Wherein R ^A represents a single, two, three, four, five, or six substituents or no substituents; R ^B represents a single, two, three, four, or four substituents; R ^A , R ^B , R ^C , R ^D And R ^E are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, and cyclic amino , Silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, thio ( sulfanyl), sulfinyl, sulfofluorenyl, phosphono, and combinations thereof; wherein n is 1 or 2; and wherein the second compound is selected from the group consisting of: For example, the composition of claim 1, wherein the vapor pressure of the first compound at 1 atm under T1 is P1, and the vapor pressure of the second compound at 1atm under T2 is P2; and wherein the ratio of P1 / P2 is between Within the range of 0.90 to 1.10. The composition of claim 1, wherein the first compound has a first mass loss rate and the second compound has a second mass loss rate, wherein a ratio between the first mass loss rate and the second mass loss rate is In the range of 0.90 to 1.10. The composition of claim 1, wherein at least one of R ^C and R ^E has the following structure: Wherein R ^F and R ^G are independently selected from the group consisting of alkyl and cycloalkyl; and at least one of R ^F and R ^G has at least two C's. The composition of claim 1, wherein the first compound has a structure according to formula IV: Wherein R ^H and R ^J are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, Cycloamino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, Thio, sulfenamido, sulfoamido, phosphino, and combinations thereof. The composition of claim 1, wherein the first compound is selected from the group consisting of: The composition of claim 1, wherein the mixture of the first compound and the second compound is selected from the group consisting of: (compound E5 and compound H1), (compound E1 and compound H14), (compound E4 and compound H21) ), (Compound E9 and compound H30), (compound E17 and compound H21) and (compound E13 and compound H33). A first device including a first organic light-emitting device, the first organic light-emitting device includes: an anode; a cathode; and an organic layer disposed between the anode and the cathode, which contains a first compound and a first A first composition of a mixture of two compounds, wherein the first compound has a chemical structure different from that of the second compound; wherein the first compound is capable of acting as a phosphorescent emitter in an organic light-emitting device at room temperature; wherein the first compound The compound has an evaporation temperature T1 of 150 to 350 ° C; wherein the second compound has an evaporation temperature T2 of 150 to 350 ° C; wherein the absolute value of T1-T2 is less than 20 ° C; wherein the concentration of the first compound in the mixture is C1 And the concentration in a film is C2. The film is evaporated in a vacuum deposition tool at a constant pressure between 1 × 10 ^-6 torr and 1 × 10 ^-9 torr to Formed at a rate of 2 Å / sec on a surface placed at a predetermined distance from the evaporated mixture, wherein the absolute value of (C1-C2) / C1 is less than 5%, wherein the first compound has structure: Wherein R ^A represents a single, two, three, four, five, or six substituents or no substituents; R ^B represents a single, two, three, four, or four substituents; R ^A , R ^B , R ^C , R ^D And R ^E are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, and cyclic amino , Silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, thio, Sulfinyl, sulfofluorenyl, phosphino and combinations thereof; wherein n is 1 or 2; and wherein the second compound is selected from the group consisting of: A method for manufacturing an organic light emitting device, the organic light emitting device includes a first electrode; a second electrode; and a first organic layer disposed between the first electrode and the second electrode, wherein the first organic layer A first composition comprising a mixture of a first compound and a second compound, the method comprising: providing a substrate having the first electrode disposed thereon; depositing the first composition on the first electrode; and The second electrode is deposited on a first organic layer, wherein the first compound has a chemical structure different from that of the second compound; wherein the first compound is capable of acting as a phosphorescent emitter in an organic light-emitting device at room temperature; A compound has an evaporation temperature T1 of 150 to 350 ° C; wherein the second compound has an evaporation temperature T2 of 150 to 350 ° C; wherein the absolute value of T1-T2 is less than 20 ° C; wherein the concentration of the first compound in the mixture is C1, and the concentration in a film is C2. The film is evaporated in a vacuum deposition tool at a constant pressure between 1 × 10 ^-6 Torr and 1 × 10 ^-9 Torr. At 2Å / sec Rate deposited to form the upper surface of the material a predetermined distance from a place where (C1-C2) / C1 absolute value of less than 5%, wherein the first compound has a structure according to Formula I: Wherein R ^A represents a single, two, three, four, five, or six substituents or no substituents; R ^B represents a single, two, three, four, or four substituents; R ^A , R ^B , R ^C , R ^D And R ^E are each independently selected from the group consisting of hydrogen, deuterium, halo, alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, amine, and cyclic amino , Silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, fluorenyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, thio, Sulfinyl, sulfofluorenyl, phosphino and combinations thereof; wherein n is 1 or 2; and wherein the second compound is selected from the group consisting of: